This invention relates to stable pharmaceutical compositions in the form of a gel which are suitable for treating acne and other androgen-related conditions, including seborrhea, hirsutism, and androgenic alopecia, in humans and which contain an antiandrogen compound dissolved or suspended in an alcohol-water solvent system and having an apparent pH value of no more than about 5 and a gelling agent
International Publication No. WO 94126767, published Nov. 24, 1994 discloses antiandrogens represented by the formula I ##STR2## wherein n is an integer of 2 to 3, pharmaceutical compositions containing such antiandrogens and methods of using such antiandrogens to treat androgen-dependent diseases including acne.
In the course of development of a pharmaceutical composition containing one of the antiandrogenic compounds of formula I, it was discovered that this compound is unstable and decomposes over time even at 25.degree. C.
Thus, there is a need for a stable pharmaceutical composition containing an antiandrogen useful for topical treatment of androgen-dependent diseases including acne and having an extended shelf life suitable for commercial use.